Justice Minister Alan Shatter has claimed former taoisigh like Bertie Ahern earn enough money from the State to pay for their own security.

Following revelations that Mr Ahern has been victimised in a number of hate attacks - including an alleged assault in a Dublin pub, the minister ruled out any review by Government for providing protection to one-time politicians.

"There are some former taoisigh who are receiving very substantial sums of money from the State who, I would think should they need an independent driver or some additional security, are in a position to arrange that themselves," Mr Shatter said.

The minister said he relies on advice from gardai as to what security measures are required by former taoisigh.

Mr Ahern, who receives a State pension of around €135,000, was allegedly attacked by a man wielding a crutch in a city centre pub on Friday.

Mr Shatter pointed out that the Government made a decision when it was fresh in office to limit the number of Garda cars used in politics.

"It was determined that it wasn't necessary that former taoisigh be driven by members of An Garda Siochana," he said.

"There are only three ministers, three members of Cabinet who for security reasons are provided with Garda cars with drivers - that's the Taoiseach, the Tanaiste and myself as Minister for Justice for security reasons."